Ever since the inception of the telephone, its use has grown dramatically year by year. At the present, the telephone is an essential tool for business and is in very widespread use in social and recreational settings. During roughly the same period of time vehicular travel has also increased dramatically both for purposes of business and pleasure. Because of the rapid growth of these two technologies and the overlap in their fields of use, it is natural that telephony and motor travel should coincide in many ways. In a business setting it is often necessary to make telephone calls while on the road, as for example to confirm meetings, secure directions and establish schedules. Likewise, in social and recreational settings it is necessary to make calls for similar reasons.
In response to the ever growing need of an increasingly mobile society to maintain a high degree of telephonic communication, public roadside phones have come into widespread use. Such phone stations usually consist of a pay telephone mounted in close proximity to the roadside and at a relatively low level so as to enable "drive-up" use.
Problems frequently occur in the use of such roadside telephones. Generally the cord linking the handset to the telephone station is made relatively short so as to prevent drivers from inadvertently departing with the handset within the vehicle. Because of the shortness of the cord it is necessary to fully lower the vehicle window in order to utilize the telephone. Additionally, the caller must remain the quite close proximity to the open window, and in some instances even lean out of the vehicle. This obviously presents many inconveniences particularly in inclement weather. The open window allows escape of heated or cooled air from the vehicle, allows entry of rain or snow thereinto and furthermore creates a relatively noisy calling environment insofar as road noise enters the vehicle. The short telephone cord also presents a further limitation insofar as passengers in the vehicle find it difficult or impossible to utilize the telephone. The short telephone cord also creates problems when drivers of trucks, busses, motor homes or other such oversize vehicles attempt to utilize roadside telephones.
In addition to the problems occasioned by relatively short cords on public roadside telephones, additional concerns arise pertaining to the transmission of infectious disease via handsets of public telephones. It is known that viruses responsible for colds, influenza and various other diseases can survive for various lengths of time upon environmental surfaces and consequently such contaminated surfaces can be sources of contagion. Accordingly, it is desirable to limit close physical contact with such surfaces.
It will thus be appreciated than, that there is a need for establishing telephone calling capabilities from the interior of a vehicle, which capabilities are not limited by the physical constraints of public telephone stations, and which do not require prolonged exposure of the vehicle interior to inclement or possibly adverse environmental conditions, and which also limit user exposure to potentially infectious surfaces.
Mobile ratio-telephone systems, commonly referred to as cellular telephones, are one solution to the foregoing problems and are presently enjoying growing public use. However, such systems tend to be very expensive and full network coverage is not available in certain parts of the country. Accordingly cellular phone systems represent only a partial solution to the foregoing problem.
What is needed is a relatively low cost device which will enable use of public vehicular telephone stations while eliminating the foregoing problems. Accordingly, there is needed a device which will enable a telephone transceiver disposed within a vehicle to interface with an external telephone station. In this manner, communication can be established via internally disposed telephone transceiver equipment thus avoiding opening the interior of the vehicle to the external environment. Such internal transceiver equipment can be disposed so as to be accessible to all passengers therewithin. It is also preferred that any such interface equipment be relatively small and portable so as to allow for ready transport from vehicle to vehicle, be low in cost and be relatively rugged.
Previously, there have been developed certain specific systems for connecting auxiliary, or extensive telephones onto pre-existing telephone circuits, so as to enable remote access to a particular telephone station. U.S. Pat. No. 3,949,172 discloses various of such systems, wherein household alternating current wiring is utilized to establish telephonic communication between a remote extension station and a master telephone circuit. The systems disclosed therein are not adaptable for use in a vehicular situation because of a lack of an electrical circuit which is common to both the vehicular telephone station and the exteriorly disposed telephone station. Therefore, there is yet a need for a system for establishing communication between an internal telephone system disposed within a motor vehicle and an external station.
The present invention, as will be described in greater detail hereinbelow provides a relatively small, inexpensive and portable interface unit adapted to be mounted upon an external portio of an automobile or other motor vehicle and capable of establishing a communication link between an internal telephone system and an externally disposed system. These and other features and advantages of the present invention will be apparent from the drawings, description and claims which follow: